POLITICIANS come in all kinds of flavours: plodders, pole-climbers, dutiful public servants, idealists, the rabid, you name it.

But in my experience there is one thing that unites them, whatever their party or policies. They are always thinking about the next election. Even if they’re barely out of one campaign, they’re already planning and calculating for the next.

There’s no need to be cynical about this. It’s fundamental to the job.

I think this universal trait helps explain Jo Swinson’s freak-out over the idea of a caretaker government led by Jeremy Corbyn to stop a no-deal Brexit.

The LibDems are going through a purple patch at the moment, their hardline on Remain lifting them to second in May’s European election with a 20.3 per cent vote share and 16 MEPs.

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Compare that to the EU election of 2014, when they were in a tuition fee hiking Coalition with the Tories, and came fifth as their vote halved to 6.9% and they crashed from 11 MEPs to one.

Ms Swinson has taken over the reins just as her party seems poised to recover its former clout and become a kingmaker again after the next election.

But that path runs through Tory turf in the south and south-west of England where Mr Corbyn is toxic and an alliance with him could scupper her dream.

At the 2017 election, the LibDems came second in 38 seats across the UK. They came behind the SNP and Plaid Cymru in single seats and behind Labour in seven. But they are the second place challengers to the Tories in 29.

They recently picked up one of those in last month’s Brecon & Radnorshire byelection, but you get the picture.

If the LibDems are to build on the momentum of the EU election, in which proportional representation greatly helped them, they must defeat sitting Tory MPs under the much tougher first-past-the-post system.

If they help install Mr Corbyn in Downing Street, even for a few days to extend the Brexit deadline and call an election, those incumbent Tories will use that against them at every turn.

You can see the posters now. A giant Nicola Sturgeon with a smaller Mr Corbyn in her pocket and Ms Swinson tucked into his, like a set of Russian dolls.

The other opposition parties will be making similar calculations about the next election too, of course. But they face less pain than the LibDems.

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The SNP are consistently high in the polls and see little threat from Mr Corbyn’s plan. Better, they may even get a sniff of Indyref2. And it’s not as if their Tory opponents in the north-east could get even angrier at the Nationalists.

Labour meanwhile would love to be able to go into an election with “Re-elect Jeremy Corbyn” as a slogan after their leader had had a dry run at the job.

So when Mr Corbyn proposed talks on a time-limited government of national unity (GNU) with him at the helm, it was understandable that Ms Swinson instantly discounted it as “nonsense”.

The Labour leader could never persuade a majority of MPs to support the idea, including many Labour MPs, far less would-be Tory rebels, so it wasn’t worth considering, she said.

Nor does she trust Mr Corbyn. Besides his endless havering on Brexit, she has said she regards him as a danger to national security and the economy.

She may be right about all of the above, but she was still wrong to dismiss it.

The proposal is a useful thing per se. It gets the ball-rolling and the parties talking. What, if anything, emerges from those talks may be a quite different plan. But the main thing for Remainers now is to put a shift in and arrive at a workable scheme. Mr Corbyn’s invitation to parley has at least got that process underway.

It also forces Remainers to face up to the fact that passing a no-confidence vote in Boris Johnson’s government is not sufficient to stop no-deal. You can’t spend half a fiver. You need a credible plan to give value to the first part.

Indeed, without knowing what comes next, Tory rebels are unlikely to vote no-confidence and end their political careers. If Remainers ever find it, the missing piece may turn out to be a GNU or emergency legislation or some other improbable novelty. No one knows. And so you have to keep all options open.

Following that logic, Nicola Sturgeon was right to say she could work with Mr Corbyn to stop no-deal. She later said she wasn’t a fan, and would prefer not to start from here, but, hey, needs must.

Even Sarah Wollaston, the former Tory MP turned LibDem, accepted the Labour leader may be “the lesser of two evils” when set against no-deal.

Suitably chided by Ms Sturgeon, Plaid and the Greens, Ms Swinson backed away from her red line and agreed to talk to Mr Corbyn after all, although she is still pushing Ken Clarke or Harriet Harman as a temporary PM.

There are a lot of mind games and brinkmanship around no-deal.

With his ‘do or die’ promise about October 31, Mr Johnson is trying to create a sense of inevitability about Brexit and instil fatalism in his opponents. The mop-topped Moses hopes they’ll part like the Red Sea and let him bumble into the promised land.

Despite leakers reportedly being threatened with the sack, his government keeps leaking tit-bits to reinforce this. Mr Johnson won’t quit after a no-confidence vote, he might delay an election to let no-deal happen, he’ll use Ireland as a pawn etc. There’s some serious posturing going on.

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But is there steel as well as bravado? How will Mr Johnson ultimately react to a concerted pushback from other parties? With so much resting on bluffing, Remainers can’t afford to rule out any means to make the PM blink.

Instead of writing off Mr Corbyn’s idea, or the next variant along, the LibDems would do better to hit the phones, fire up a spreadsheet, and start listing names against the various options to see which one could command a majority after a no-confidence vote.

They also need to gird themselves for the possibility that Mr Corbyn’s plan is required as a last resort, whatever the immediate electoral fall-out for them.

A broken promise on tuition fees trashed the LibDem brand for most of a decade. If the party also let an avoidable no-deal Brexit take place when it might have acted, it would never recover.